ISO's short wavelength spectrometer ultimate sensitivity - Reducing the effects of cosmic weather

Compared to the pre-launch measurements, the in-orbit noise levels of the S hort Wavelength Spectrometer (SWS) detectors show a significant increase, c onsiderably lowering the overall sensitivity. Cosmic ray impacts on the det ectors and/or on the instrument electronics play an important role in the n oise levels and consequently many observations of faint sources are affecte d by this increased noise. However, by taking advantage of the high read-ou t frequency of 24 Hz and the redundancies provided by the observing strateg y, it is possible to significantly improve the quality of the data. Here, w e present the concept of self-calibration and additional algorithms, which are successfully applied to recover the weak signals of molecular hydrogen lines undetectable in a standard data reduction.